Pneumatic action for musical instruments.



C. J. MONFREDINI.

PNEMATIG ACTION POR `MUSICAL INSTRUMENTS.

APPLICATION PILBD'APRA, 1913.

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ms@ I af oALIsTo'J. MONFREDINI, or Boeren, MASSACHUSETTS.

PNEUMTIC ACTION FOR MUSICAL INSTRUMENTS.

Specification of Letters Patent. I Patent-@d Ninn 18,1913,

Application led Apr14, 1913'. Serial No. 758,817.

To altr/ahoga t may concern: l

Be it knowntha-t I, CALIs'ro J. MONFRE- nini, a subject of the 'King of Italy, resid:

ing at'Boston, in the county of Suffolk and State' OfMaS'SachuSettS, Ahave invented new 'and useful Improvement-s in Pneumatic Actions .for Musical Instruments, of which the following is'a specification.l

This invention relates to pneumatic actions formusical instruments and has for its objectthe producing of lan inexpensive, com pact and durable device for controlling the action of the tone producing instrumentalities,.said device being detachably secured inplace to permit its removal to inspect and repair the'various parts thereof.

The invention consists in the combination vand arrangement of `parts whereby the above object and certain other objects hereinafter appearing may be attained, as set forth 1n the following specification and particularly pointed out in the claims.

Referring to the drawings:.Figure 1 is a rear elevation of a portion of a pneumatic action embodying my invention, parts of said device being shown in section and other parts broken away to more clearly illustrate the same. Fig. 2 is a sectional elevationtaken on line 2-2 of Fig. l1.

Like numerals refer to like parts throughout the severalviews of the drawings.

' usual v manner.

In the drawings,4 is asuction chest which is of the usual form and arranged longitudinally of the instrument of which the device forms a part, andcomprising a chamberv from which .the air is exhausted inthe Connected tothe suction chest 1, preferably 'to the bottom thereof, is a series vof. bellows 6 the movable member 7 of which is connected through a link 8 to the tone producing instrumentalitiesin the' usual manner. A tracker board 9preferably of the. usualsconstruction, isY connected by means ofA a tube 10 to an'air passage ll'preferably extending through the lower portion of the suction-Cheste, said tracker board coperating with the mus-ic sheet 12 in permitting air to enter saidsuction chest through the tube 10'and'air,.passage-11,.ab the proper time:

1 The suction chest 4: provided with pas sages 13 which leadfrom the-suction cham- ,l ber` 5 outwardlytofthe outer wall14 of said chest, said passages 13 .being uniformly spaced `thramghout the length .ofsaid 'suctionchest. The air passage 11 also extends '6, 'said passages 13, 11 and 15 ofthe respective sets being arranged substantially in the l same vert-ical plane. A valve' shell 16 is detachably secured in contact with the wall 14 of'said suction chest to cover all of said passages included in one set, said shell. be-

ing secured to said chest by means of screws 17 extending through plates 18 arranged transversely of said shells, the distances be tween the centers of one set of passages and the next adjacent sets of passages being preferably equal to the diameters of said shells, thus permitting said shells to be arranged in contact with said chest and in contact with the adjacent shells.

The valve shell 16 is also provided with a suction chamber 19 which is a continuation of the passage 13 connecting Said suction chamber with the main suction chamber 5. Leading outwardly from the suction chamber 19, substantially in opposite directions, are ports 2O and 21, said ports beingY providedwith disks 22 and 23 respectively which are adapted to close said ports during certain times in the operation of the device.

The valve disk 22 is preferably secured to a diaphragm 24 which is arranged Withina chamber 25 formed in said shell 16 above a recess 26, while the valve 23 is secured to a valve stem 27 which is reciprocatorily arranged in guides 28 and ,29, mounted in the ports 20 and 21 respectively, said valve stem vnormally contacting with the -disk 22 and adapted to be moved by saiddisk upon the deflection of the diaphragm 24. The recess 26is connected by means of a passage 30 with the chamber 25, while a seco-nd passage 31 connects said .recess 26 with' the air passage 11, all of said passages unit-ing to provide lcommunication between said tracker board and said suction chamber 5, said passages 30 and 31 being arranged within the shell 16, but particularly in a detachable diaphragm supporting mein.v .ber 32 whichcontains said recess 26' and the diaphragm 24: permitting the removal of" saidfdiaphragm from said shell to replace the same, said member being preferably held, at oneside thereof, in place in said shell. by a tapering side 33 which engages a correspondingly tapering wall 34 oi' the ing an air inlet passage 37 extending longitudinally of said cap and in a-linement with the median axial line ,of the valve stem 27, while a series of laterally disposed ports 38 constitute the mouth of said inlet passage. The lower end ofthe c'a 36 constitutes a seat for the valve 23 w en said valve is moved by the deflection of thev diaphragm 24, thus closing said inlet passage whensaid valve is seated thereagainst. -v

Y The general-operation of the device hereinbefore specifically described is as follows;`

The air in the suction chamber '5 isy exhausted in a manner wellknownto those. skilled in the art and as .long as said suction is maintained and air is admitted to said lshell .through noother sourcethanthe passage`27, there will be a tendency, by reason thereof, for the valve .23 to remain in contact with the partition;l in the shelly 16 com-4 prising Vthe port 21 thus closing -said port. Furthermore the suction in said chamber acting through the port 20, chamber 25, pas-v sage 30 and recess 26 tends to retain the diaphrag'm 24 in its position indicated in full linesFigs. 1 and 2, providing no air is permitted to enter the passage 1l. When however the music sheet 12 is moved to bring one of the perforationsa therein into alinement with the hole b in the tracker board 9 the air at atmospheric pressure will be suddenly forced,'in its attempt to enter the suction4 chamber 5 through the tube 10 and air passage 11 into the recess 26 beneath and againstsaid diaphragm 24, certain portions kof said air escaping through the passage 30 which is substantially smaller in area than the air passage 31. In consequence of the phrough withthe exception of a very 'smallalacant which may leak therethrough Qwing.

difference in areas between the diaphragm 24 and the. valve disk 23 said diaphra m which is the lar e1 will be deflectedy andy lsaid deflection evalve 22 will be moved from its position illustrated in full lines Figi'2 tonthat illustrated in'dotted lines,in said'figure'or, against the partition comprisin the r`port"`i20 yand thereby close said port an preventing the admission of air there to the impossibility of making a valve' of this `nature absolutely air tight." This leak!` -agelaoweveris necessary in the operation of the device asit removes a certain amount of airfromthechamher l25, which has entered saidchamber through the passage 30. Itv

would seem in view of this statement that the'valve 22 would be-un'necessary. This fvalve however is provided for the purpose ofl llimiting the amount of air which may be drawnthrough the port 20 at a time when thel opening in the` music sheet 'almes with the passage b, for should the air bey permitted to'be uninterruptedly drawn through l the port 20 the suction creating devices Awould be unduly taxed or rendered inadequate to maintain a suction in the chamber 5 suiiicient'to collapse the bellows G.V Then again if the passage 30 were to be made Smaller in order to limit the amount of air assing therethrough the return movement of the diaphragm would `be retarded.

Simultaneously with the' closing of the port 20 the port 21 will be opened by reason of the fact that-the stem 27, which carries the' valve 23, contacts with the face of the valve 22, and as ,said valve moves upwardly the valve '23 will likewise be moved from its position illustratedin full lines Fig. 2 to that illustrated in dotted lines in said igure and into c'ontact with the under :tace of the cap 36Ty By the closing of the passage 37 by the valve 23.*in its upward movement the s/upply of air through said'passage into the main suction channel 35 will beycut oil and the air remaining in said passage will be exhausted through the port 21, by means of the suction in the suction chamber 5, and by this action thebellows 6 will be collapsed, that is to say, the movable member 7 will be drawn toward the stationary member 39 and actuate the tone producing instrumentalities through the link 8 in the usual manner, not shown in the drawings, the pressure atthis time afrainst the diaphragm 24 being greater than that against the valve 23, thereby overcomes the tendency of the valve 23 to descend. In this condition the valves are maintained as long as the perforations in the musicsheet l2 aline with the hole b permit-ting the air to enter therethrough, but as said music sheet moves along over said opening 'and gradually closes the same, the

'supply ofair will be cut 0E through the passage '11 and t e pressure of the air through the holes 38 and passage 37 will overcome the pressure against the., diaphragm 24 owing, as hereinbefore stated, to the exhaustion of the air in the chamber 26 through the passage 30 and port 20 even though `the valve 22 be closed and cause a reactlon. thereof which results in the closing of the ports 21 by thev valve 23 and permitting the air to rush through the ports 38 and suction channel 35 into the bellows 6, causing-the same to open as indicated in Fig. 2, which is the" normal condition thereof.

when. it is desired a replace the, disk 23,V

i may then be withdrawn without disturbing any of the associated parts of the device.

To remove the disk 22 or the diaphragm 24 from any one of the shells 16, the screw 17 which secures that shell in contact with 'the suction chest are removed and said shell `withdrawn from contact with the face 14. This operation exposes the member 35 which may be removed from the chamber 25 and said'disk 22 will be exposed ,rections, valves for said ports respectively,

and a diaphragm adapted to be moved by the passage of air through said tracker boards to operate said valves to close one' and` open `the other of said ports.

2. A-pneumatic action for musical instruments having, in combination, a suction chest,l a bellows, a tracker board, a valve shell detachably secured to said chest comprising two ports opening into said chest, one of said ports being connected by a channel extending through said shell to said bellows, the other of said nected by passages extending through said shell to said tracker board, a valve for each of said ports respectively, and a diaphragm arranged within said shell adapted to be moved in one direction by the admission of air through the port connected with said tracker board to close that port and open the' port connected with said bellows, said diaphragm adapted to be moved in the opposite the cutting off of the lsupply or' direction by air from said tracker board, to move said valve inthe opposite direction.

3. .A pneumatic action for musical instruments embodying, in its construction, a

valve shell having a chamber open at one side thereof, the wall of said chamber cpposite said opening inclining inwardly from the bottom of said chamber upwardly, and

-a diaphragm supporting member detachably arranged within said chamber, the inner side of said support engaging said inclined wall and the outer side of said support alining with the open side of said shell, whereby said member may be retained in its proper position.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses., f

CALISTO J. MONFREDINI.

lVitnesses:

SYDNEY E. TAFT, PAUL C. JARBONNIER.

Copies of this patent may be obtained for ive cents each, by addressing the Commissioner of Patents,

Washington, D. C.

ports being con- 

